Model TFC1K – Fixed Tuned Circular Polarized Antenna
Tuning Stubs, 4 per antenna
(2 long for low band, 2 short for high band)
Interbay feed line if more than single bay
These antennas may be used from 88 – 108 MHz depending on the tuning stub used. Use the longer stubs for 88 – 98 MHz. The short stubs should be used at 98 – 108 MHz. IMPORTANT: Save the extra stubs in case the antenna must be used on a different frequency.
Tuning stubs must be mounted on each bay before energizing antenna. The clamp should be positioned at the end of the stub for proper electrical conductivity and maximum rigidity.
The shorting strap can be adjusted for minimum reflected power on each bay after all parts are in place.
DO NOT CUT OR SHORTEN THE RG-213 INTERBAY FEED LINES. They must all be the same length for proper phasing and power distribution of the antenna. Excess cable can be curled and tied into place on the tower.
Make sure that the hardware is tightened securely and evenly.
Mount antenna clear of any obstructions on a pipe or tower leg up to 4″ O.D.
Connect the feed line to the antenna. Make sure that there is no undo strain on the antenna and that there is not any type of mechanical bind.
Energize the antenna at a very low power level to check for open circuits, shorts or other errors. Slowly increase the power level watching both forward and reflected power. Reflected power should always be 10% or less of forward power or damage to the transmitter and/or antenna may result. When properly installed VSWR should be less than 1.5 to 1 across the FM band.
Spacing of multiple bays: Spacing between bays (Wavelength) in inches = 11803 divided by the Frequency in MHz.